Under-engineering makes it hard to fix common issues because there is no common code to fix. You can find yourself scouring over thousands of lines of code nev

Under-engineering makes it hard to fix common issues because there is no common code to fix. You can find yourself scouring over thousands of lines of code never sure that you found all the places you need to find. This is why DRY is a solid principle. I think there is always the problem that programmers want to apply all these principles, including DRY, without actually thinking about it. Once it's applied illogically you are in strange and awful territory.